Hibiscus (Hibiscus sabdariffa)
Summary
Hibiscus sabdariffa, drunk as sour tea or taken as extract, has been tested for blood pressure. Pooled trials found systolic pressure about 7 mm Hg lower than placebo, with the largest falls in people starting with high blood pressure, and effects similar to some medicines in head-to-head trials. Trials were small and heterogeneous, and optimal dose and duration are unknown.
Key facts
- A tropical plant rich in organic acids, polyphenols and anthocyanins, usually consumed as a tea[1]
- 5 trials (390 people): systolic −7.58 and diastolic −3.53 mm Hg; larger effects with higher starting pressure[1]
- 17 trials: systolic −7.1 mm Hg versus placebo, and no significant difference from blood-pressure medication[2]
- LDL about 6.8 mg/dL lower than with other teas or placebo[2]
- 1 graded human outcome on this page
- October 11, 2026
How it works
ProposedHow hibiscus lowers blood pressure is not established in the sources cited here; its polyphenols and anthocyanins are the proposed active components.[1]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Systolic and diastolic blood pressure | Improved | Grade C | Meta-analysis · n = 390 · 2015 Adults in 5 randomized trials, mostly with hypertension Form: Hibiscus sabdariffa tea or extract · Dose: Varied across trials · Duration: Varied across trials Systolic pressure fell 7.58 mm Hg and diastolic 3.53 mm Hg versus control, with larger falls at higher baseline pressure. | 25875025 (opens PubMed)Source [1] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Hibiscus (sour) tea | Varies | No head-to-head human absorption data in the sources cited here. | No form-specific tolerance data in the sources cited here. | Blood-pressure trials |
| Hibiscus extract (capsules) | Varies | No head-to-head human absorption data in the sources cited here. | No form-specific tolerance data in the sources cited here. | Blood-pressure trials |
Studied doses
Doses studied in human trials ranged from trial to trial across teas and extracts; the reviews cited here say the effective dose and duration are not yet established.[2][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- People on blood-pressure medicines
- Hibiscus lowered blood pressure about as much as medication in head-to-head trials, so effects could add up.[2]
- Low blood pressure
- Pooled trials showed meaningful falls in blood pressure.[1]
- Pregnancy and breastfeeding
- Not studied in these groups in the trials cited here.[2]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Frequently asked questions
Does hibiscus tea lower blood pressure?
Pooled trials found about 7 mm Hg lower systolic pressure, most in people with high readings to start.[1][2]
Is hibiscus as good as blood-pressure medicine?
In head-to-head trials the difference was not significant, but trials were small; it is not a substitute for prescribed treatment.[2]
Does hibiscus lower cholesterol?
LDL was about 6.8 mg/dL lower than with other teas or placebo.[2]
How much hibiscus should be used?
The reviews say the effective dose and duration are not yet established.[2]
Sources
- [1]Effect of sour tea (Hibiscus sabdariffa L.) on arterial hypertension: a systematic review and meta-analysis of randomized controlled trials. J Hypertens, 2015. meta-analysis
- [2]A systematic review and meta-analysis of the effects of Hibiscus sabdariffa on blood pressure and cardiometabolic markers. Nutr Rev, 2022. meta-analysis
What changed
- New monograph. Every PMID checked against NCBI E-utilities (title, journal and year from the PubMed record); each evidence row written from its abstract; intake and safety facts from the cited fact sheets.